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Embedded resistor

Calculate an embedded resistor’s resistance from its length, width and sheet resistance.

Inputs

Results update as you change the inputs.

Material
Ω/sq

The process type is shown for reference. Check the sheet resistance in the material datasheet.

Geometry
mm
mm
V

Result

Enter your values to calculate a result.

Length, width and sheet resistance
Length, width and sheet resistance

The ratio L/W gives the number of squares. Multiply this by the sheet resistance to find the resistance between the terminals. The illustration shows a uniform rectangular film.

Illustration only. Not to scale.

Resistance

N/A

SquaresN/A
Resistor areaN/A
Sheet resistanceN/A
Power at voltageN/A
Method and assumptions

R = Rsheet × L / W. The number of squares is L/W.

  • Contact resistance, trimming and process tolerance are not included.
  • Use the material datasheet and the PCB manufacturer's process data for production values.
  • Power is only calculated when an applied voltage is entered.

Find resistance from the number of squares

The resistance is set by the number of squares and the material sheet resistance. Increase length or reduce width to increase the number of squares. The process type does not change the ideal geometry calculation.